1. Field of the Invention
The present invention is related to information handling systems, and more specifically, to controlling the ability to back-flash a BIOS when new features are present on the information handling system.
2. Description of the Related Art
As the value and the use of information continue to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores and/or communicates information or data for business, personal or other purposes, thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems, e.g., computer, personal computer workstation, portable computer, computer server, print server, network router, network hub, network switch, storage area network disk array, redundant array of independent disks (“RAID”) system and telecommunications switch.
Most computer systems include a basic input output system (commonly referred to as “BIOS”) that provides an interface between the operating system kernel and the underlying hardware. The kernel is the portion of the operating system that is closest to the application software. The kernel is responsible, typically, for process control, memory management, file management and peripheral support. The kernel passes commands from the application software to the BIOS for translation into hardware-specific requests.
BIOS is firmware for personal computers (“PC's”) that is responsible for initializing when it is first switched on or reset. The major task of the BIOS is to load and begin execution of the operating system that is normally stored on the computer's hard disk. The BIOS also provides a low level interface to the peripheral devices of the computer system. The BIOS is stored in a non-volatile memory that can be updated, or in a read-only-memory (“ROM”).
While the BIOS is responsible for checking of the system at startup time, a particular version of the BIOS does not necessarily support all of the hardware's capabilities. BIOS designers cannot conceive of all of the hardware that may be added to the system at a later date. For many years, BIOS code has been made extensible through the use of flash memory chips. This ability to program the BIOS after it has been installed forestalls the obsolescence of BIOS chips as new hardware features are installed. In this way, the BIOS can be updated by modem, network, or directly from a diskette to bring the BIOS code in line with new hardware capabilities.
In the case of servers, new features such as new CPU steppings, new memory sizes, new flash type and architectures are required to be supported post-installation and throughout the life of the product via BIOS updates. In the past, if problems were encountered with the updated BIOS, system operators would back-flash to an older BIOS revision, and thus incur incompatibilities with newer features that were installed on the server. In some instances, back-flashing can prevent the server from booting at all, with obvious consequences.
For example, consider the case of a platform currently shipping with DELL® A01 BIOS, which is available from Dell Inc. of Round Rock, Tex. The BIOS, then, may get revised to support, for example, new 2GB dual in-line memory modules (“DIMMs”) or a new stepping of processor that requires new microcode update patches, or support for a new flash part due to part availability. It would then be desirable for the user to implement the updated DELL® A02 BIOS to support the new features. As required, a customer who gets a system with A02 BIOS, with one or all of these enhancements, would need to be blocked from back-flashing to A01 BIOS since A01 BIOS does not support these new features or enhancements and back-flashing could result in an unusable system, for example, there would be no memory or corrupted flash due to a new architecture of flash part.
Simply preventing all back-flashes, however, prevents any customer, even one who does not have any of the new technologies installed, or an existing customer who upgrades from A01 to A02 BIOS, from back-flashing to A01 BIOS altogether. Therefore, a problem exists, and a solution is required for determining whether a BIOS back-flash should be enabled on a computer system.